Changed graphics card no signal

[Hubabaluba]

Tried installing a new graphics card to replace the AMD R9 270, however, after booting up with new graphics card, monitor showed no signal while the rest of the system seemed to be working fine. Tried using HDMI, DP and VGA, all without any success. Tried another graphics card, and it didnt work either. The thing is that both graphics cards works in other systems. 

[DGroves]

hmmmm,....the  R9 270 is a unique card as it shipped in both Legacy and later on with legacy/UEFI capable bios, many of the retail legacy models had bios updates to upgrade them to Legacy/UEFI

it's possible your original OEM card or motherboard  is configured for, or is Legacy onlY? if ( this is the case you might be able to update the motherbios check hp site for this possibility

before you do that reinstall the orig card, and check the existing bios settings for UEFI and CSM settings both should be enabled

other than a possible uefi config issue your system should be able to run later cards

https://support.hp.com/ph-en/document/c04574072

[Paul_Tikkanen]

Hi, @Hubabaluba

I agree with DGroves' opinion that the OEM card was made by AMD specifically for your PC's model series, and as such, its properties have been added to the secure boot keys in the BIOS.

Whenever you install a non-HP video card in any HP PC that came with W8 or newer, you have to change a couple of BIOS settings.

I suggest you try enabling legacy mode, disabling secure boot, and see if you can get the non-HP video card to work.

See this link for the settings to change.

https://support.hp.com/us-en/document/c03653200/

[Hubabaluba]

I disabled secure boot and enabled legacy support, yet when installed the desired graphics card, it still didnt seem to work. As for the BIOS, I'd already updated it to AMI A0.13, which seems to be the newest version.